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Abstract:

A light emitting device includes a light emitting element and a package.
The package is made up of a molded article and a lead that is embedded in
the molded article. The lead includes a mounting part on which the light
emitting element is mounted, a terminal part that is linked to the
mounting part, and an exposed part. The package has a front face that is
a light emitting face, a rear face opposite the front face, and a bottom
face contiguous with the front face and the rear face. The light emitting
element is mounted on the front face side of the mounting part. The
exposed part is linked to the rear face side of the mounting part, and is
exposed from the molded article at the bottom face and the rear face. The
terminal part is exposed from the molded article at the bottom face.

Claims:

1. A light emitting device, comprising: a light emitting element; and a
package constituted by a molded article and a lead embedded in the molded
article, the lead including a mounting part, a terminal part and an
exposed part, the light emitting element being mounted on the mounting
part, the terminal part being linked to the mounting part, the package
having a light emission face, a rear face opposite to the light emission
face, and a bottom face communicating the light emission face and the
rear face, the light emitting element mounted on a light emission face
side of the mounting part, the exposed part linked to a rear face side of
the mounting part, the exposed part being exposed from the molded article
at the bottom face and the rear face, and the terminal part exposed from
the molded article at the bottom face.

2. The light emitting device according to claim 1, wherein the exposed
part has a concave component that continuously opens on the bottom face
and the rear face.

3. The light emitting device according to claim 2, wherein the concave
component extends in a first direction parallel to a boundary between the
bottom face and the rear face.

4. The light emitting device according to claim 3, wherein the exposed
part has a partition that divides an interior of the concave component
into two spaces arranged in the first direction.

5. The light emitting device according to claim 1, wherein the lead
includes an extension that is disposed on the mounting part and is
exposed from the molded article at the rear face, and the extension is
connected to the terminal part.

6. The light emitting device according to claim 1, wherein the terminal
part is exposed from the rear face, and the exposed part is larger than
the terminal part in a plan view of the rear face.

7. The light emitting device according to claim 1, wherein the exposed
part is disposed on an opposite side from the light emitting element with
the mounting part in between.

8. A circuit board, comprising: a light emitting device; a mounting board
on which the light emitting device is mounted; and a first solder fillet
and a second solder fillet disposed on the mounting board, the light
emitting device having: a light emitting element; and a package
constituted by a molded article and a lead embedded in the molded
article, the lead including a mounting part, a terminal part and an
exposed part, the light emitting element being mounted on the mounting
part, the terminal part being linked to the mounting part, the package
having a light emission face, a rear face opposite to the light emission
face, and a bottom face communicating the light emission face and the
rear face, the light emitting element mounted on a light emission face
side of the mounting part, the exposed part linked to a rear face side of
the mounting part, the exposed part being exposed from the molded article
at the bottom face and the rear face, the terminal part exposed from the
molded article at the bottom face the first solder fillet connected to
the terminal part and the mounting board, and the second solder fillet
connected to the exposed part and the mounting board.

9. The circuit board according to claim 8, wherein the exposed part has a
concave component that continuously opens on the bottom face and the rear
face, the concave component includes an inner wall that intersects a
first direction parallel to a boundary between the bottom face and the
rear face, the second solder fillet is connected to the mounting board
and the inner wall, and a light emitted by the light emitting element is
emitted along a second direction perpendicular to the rear face.

10. A package array for a light emitting device, comprising: a molded
board made of resin; and a lead frame embedded in the molded board, the
lead frame formed in a thin plate shape, the lead frame having a first
frame component and a second frame component adjacent to the first frame
component in a specific direction, the first frame component and the
second frame component each including: a first thick part exposed from
the molded board with a first thickness; a second thick part exposed from
the molded board with the first thickness, the second thick part
separated from the first thick part in the specific direction; a first
thin part linked to the first thick part and the second thick part with a
second thickness less than the first thickness; and a second thin part
linked to the second thick part with the second thickness, the second
thin part separated from the first thin part in the specific direction.

11. The package array for a light emitting device according to claim 10,
wherein the lead frame has a third frame component and a fourth frame
component that have the same configuration as the first frame component
and second frame component, the third frame component and the fourth
frame component are disposed in rotational symmetry to the first frame
component and the second frame component around an axis parallel to a
thickness direction, the first thick part of the third frame component is
linked to the first thick part of the first frame component, the second
thick part of the third frame component is linked to the second thick
part of the second frame component, and the second thick part of the
fourth frame component is linked to the second thick part of the first
frame component.

12. The package array for a light emitting device according to claim 10,
wherein the lead frame has a third frame component and a fourth frame
component that have the same configuration as the first frame component
and second frame component, the third frame component is adjacent to the
first frame component in a perpendicular direction perpendicular to the
specific direction, the fourth frame component is adjacent to the second
frame component in the perpendicular direction, the first thick part of
the third frame component is linked to the first thick part of the first
frame component, the second thick part of the third frame component is
linked to the second thick part of the first frame component, the first
thin part of the fourth frame component is linked to the first thick part
of the second frame component, and the second thin part of the fourth
frame component is linked to the second thick part of the second frame
component.

13. A method for manufacturing a package array for a light emitting
device, comprising: a double-sided etching step of forming etching holes
in a thin metal plate by etching a first main face and a second main face
opposite to the first main face of the thin metal plate; a one-sided
etching step of forming a lead frame in a specific shape by forming an
etching concave component in a second pattern on the first main face, the
etching concave component is formed by etching part of the first main
face of the thin metal plate; and a molding step of forming a molded
board in which the lead frame is embedded by injecting resin into a metal
mold in which the lead frame is disposed, wherein the lead frame has a
thick part that constitutes an exposed part linked to a mounting part for
mounting a light emitting element, and a thin part that constitutes a
connected part separated from the mounting part with the etching holes in
between.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Japanese Patent Application No.
2010-198371 filed on Sep. 3, 2010 and Japanese Patent Application No.
2010-253159 filed on Nov. 11, 2010, the disclosures of which are hereby
incorporated herein by reference in their entirety.

TECHNICAL FIELD

[0002] The technology disclosed herein relates to a light emitting device
equipped with a light emitting element, and to a circuit board comprising
the light emitting device and a mounting board.

BACKGROUND INFORMATION

[0003] As the output of light emitting elements (such as light emitting
diodes or laser diodes) used in LCD television backlights, lighting
fixtures, optical communications devices, and so forth has risen in
recent years, there has been a need for a technique with which heat can
be efficiently dissipated from the light emitting element.

[0004] There is a known light emitting device comprising a light emitting
element and a package in which the light emitting element is mounted (see
Japanese Laid-Open Patent Application Publication No. 2010-62272, for
example). The package has a molded article made of resin and so on, and a
metal lead that is embedded in the molded article. The lead includes a
mounting part on which the light emitting element is mounted, and a
terminal part that is linked to the mounting part and is connected to a
mounting board via a solder fillet.

SUMMARY

[0005] With this light emitting device, the thermal transmittance of the
molded article is far lower than that of the lead, so a path that leads
to the mounting board via the mounting part, the terminal part, and the
solder fillet, in that order, is dominant as the heat dissipation path
from the light emitting element.

[0006] However, because of the small surface area of the portion of the
terminal part that is exposed from the molded article, and because of the
long distance from the light emitting element to the terminal part, it is
difficult to achieve efficient heat dissipation from the light emitting
element when the above-mentioned path is dominant.

[0007] The technology disclosed herein was conceived in light of the above
situation and is an object thereof to provide a light emitting device, a
circuit board, a package array for a light emitting device, and a method
for manufacturing a package array for a light emitting device, with which
heat can be efficiently dissipated from the light emitting element.

[0008] The light emitting device disclosed herein comprises a light
emitting element and a package. The package is constituted by a molded
article and a lead embedded in the molded article. The lead includes a
mounting part, a terminal part and an exposed part. The light emitting
element is mounted on the mounting part. The terminal part is linked to
the mounting part. The package has a light emission face, a rear face
opposite to the light emission face, and a bottom face communicating the
light emission face and the rear face. The light emitting element is
mounted on a light emission face side of the mounting part. The exposed
part is linked to a rear face side of the mounting part. The exposed part
is exposed from the molded article at the bottom face and the rear face.
The terminal part is exposed from the molded article at the bottom face.

[0009] The technology disclosed herein can provide a light emitting
device, a circuit board, a package array for a light emitting device, and
a method for manufacturing a package array for a light emitting device,
with which heat can be efficiently dissipated from the light emitting
element.

BRIEF DESCRIPTION OF DRAWINGS

[0010] FIG. 1 is an oblique view of a light emitting device 100 pertaining
to a first embodiment, as seen from the front;

[0011] FIG. 2 is an oblique view of the light emitting device 100
pertaining to the first embodiment, as seen from the rear;

[0012] FIG. 3 is a see-through view of FIG. 1;

[0013] FIG. 4 is a see-through view of FIG. 2;

[0014] FIG. 5 is a plan view of a bottom face 20A of the light emitting
device 100 pertaining to the first embodiment;

[0015] FIG. 6 is a plan view of a first side face 20D1 of the light
emitting device 100 pertaining to the first embodiment;

[0016] FIG. 7 is an oblique view of the mounting face of a mounting board
200 pertaining to the first embodiment;

[0017] FIG. 8 is an oblique view of the mounting face of a circuit board
300 pertaining to the first embodiment;

[0018] FIG. 9 is a diagram illustrating a method for manufacturing the
circuit board 300 pertaining to the first embodiment;

[0019] FIG. 10 is a diagram illustrating a method for manufacturing the
light emitting device 100 pertaining to the first embodiment;

[0020] FIG. 11 is a detail view of a lead frame 45 pertaining to the first
embodiment;

[0021] FIG. 12 is a cross section along the A-A line in FIG. 11;

[0022] FIG. 13 is a diagram illustrating a method for manufacturing the
light emitting device 100 pertaining to the first embodiment;

[0023] FIG. 14 is an oblique see-through view of the light emitting device
100 pertaining to the second embodiment, as seen from the rear;

[0024] FIG. 15 is a diagram illustrating a method for manufacturing the
light emitting device 100 pertaining to the second embodiment;

[0025] FIG. 16 is an oblique view of a mounting board 200 pertaining to
the third embodiment, as seen from a mounting face side;

[0026] FIG. 17 is an oblique view of a circuit board 300 pertaining to the
third embodiment, as seen from the mounting face side;

[0027] FIG. 18 is an oblique see-through view of the light emitting device
100 pertaining to the fourth embodiment, as seen from the rear;

[0028] FIG. 19 is a diagram illustrating a method for manufacturing the
light emitting device 100 pertaining to the fourth embodiment;

[0029] FIG. 20 is an oblique see-through view of a light emitting device
100 pertaining to a fifth embodiment, as seen from the rear;

[0030] FIG. 21 is a diagram illustrating a method for manufacturing the
light emitting device 100 pertaining to the fifth embodiment;

[0031] FIG. 22 is a detail view of a lead frame 45C pertaining to the
fifth embodiment; and

[0032] FIG. 23 is a diagram illustrating a method for manufacturing the
light emitting device 100 pertaining to the fifth embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

[0033] Embodiments of the present invention will now be described through
reference to the drawings. In the discussion of the drawings below,
portions that are the same or similar will be given the same or similar
numbers. The drawings, however, are merely representations, and the
proportions of the various dimensions may vary from those in actuality.
Therefore, specific dimensions and so forth should be decided on by
referring to the following description. Also, the dimensional relations
and proportions of some portions may, of course, vary from one drawing to
the next.

FIRST EMBODIMENT

Summary of First Embodiment

[0034] In the first embodiment, we will describe a light emitting device
with which heat can be efficiently dissipated from the light emitting
element, and a circuit board comprising this light emitting device and a
mounting board. More specifically, the light emitting device has an
exposed part that functions as a heat sink to promote the dissipation of
heat from the light emitting element.

[0035] The configuration of the light emitting device, mounting board, and
circuit board, and the method for manufacturing the light emitting
device, will now be described in order.

Configuration of Light Emitting Device

[0036] The configuration of the light emitting device pertaining to the
first embodiment will be described through reference to the drawings.
FIG. 1 is an oblique view of a light emitting device 100 pertaining to
the first embodiment, as seen from the front. FIG. 2 is an oblique view
of a light emitting device 100 pertaining to the first embodiment, as
seen from the rear.

[0037] The light emitting device 100 comprises a light emitting element 10
and a package 20. The light emitting device 100 pertaining to this
embodiment is what is known as a side-view type of light emitting device,
and light emitted from the light emitting element 10 is taken off in a
direction parallel to a mounting face 200A (see FIG. 7) of a mounting
board 200 (discussed below).

[0038] In this embodiment, the light emitting device 100 has a
substantially cuboid shape that extends along a first direction parallel
to the mounting face 200A. However, the outer shape of the light emitting
device 100 is not limited to this, and may be a cubic shape, a circular
cylindrical shape, an elliptical cylindrical shape, or the like.

[0039] In this embodiment, the size of the light emitting device 100 is
approximately 3 mm in the first direction, about 1 mm in a direction
parallel to the mounting face 200A and perpendicular to the first
direction (hereinafter referred to as the "second direction"), and about
1 mm in a direction perpendicular to the first direction and the second
direction (that is, a direction perpendicular to the mounting face 200A;
hereinafter referred to as the "third direction"). The size of the light
emitting device 100 is not limited to this, however.

[0040] The light emitting device 100 pertaining to this embodiment,
however, is a side view type, and its height in the third direction is
greater than its depth in the second direction. Therefore, the side
view-type light emitting device 100 is taller than a top view type of
light emitting device in which the height in the third direction is less
than the depth in the second direction, so it is characterized by a
tendency to topple.

Light Emitting Element 10

[0041] The light emitting element 10 is placed in the package 20. The
light emitting element 10 is electrically connected to the package 20 via
a first wire 11 and a second wire 12.

[0042] The light emitting element 10 is formed in a flat shape, and is
disposed perpendicular to the second direction. The emitted light from
the light emitting element 10 is taken off in a direction parallel to the
second direction, from a front face opening 20E (discussed below).

[0043] The light emitting element 10 is a semiconductor light emitting
element called a light emitting diode, for example. The light emitting
element 10 preferably has as its light emitting layer a semiconductor
such as GaAlN, ZnS, SnSe, SiC, GaP, GaAlAs, MN, InN, AlInGaP, InGaN, GaN,
or AlInGaN on a substrate, but is not limited to this.

[0044] A face-up structure or a face-down structure can be employed for
the light emitting element 10. There are no particular restrictions on
the size of the light emitting element 10, but examples include 350 μm
square, 500 μm square, and 1 mm square.

Package 20

[0045] In this embodiment, the package 20 has a substantially cuboid shape
that extends in the first direction. The package 20 has a bottom face
20A, a top face 20B, a front face 20C, a first side face 20D1
(corresponds to the "rear face" of the side-view light emitting device
100), a second side face 20D2, and a third side face 20D3.

[0046] The bottom face 20A hits the mounting face 200A (see FIG. 7) when
the light emitting device 100 is mounted. The top face 20B is provided
opposite the bottom face 20A. The front face 20C is a light emission face
that is contiguous with the bottom face 20A and the top face 20B. The
front face 20C has a front face opening 20E. The front face opening 20E
guides the light emitted from the light emitting element 10 to outside
the package 20. The light emitting element 10 is placed on a mounting
face 41A (see FIG. 3) exposed in the interior of the front face opening
20E. The first side face 20D1 is contiguous with the bottom face 20A
and the top face 20B, and is provided opposite the front face 20C. The
first side face 20D1 is perpendicular to the second direction (that
is, a direction in which the light emitted by the light emitting element
is taken off). The boundary between the first side face 20D1 and the
bottom face 20A is parallel to the first direction. The second side face
20D2 is contiguous with the first side face 20D1 and the front
face 20C. The third side face 20D3 is provided opposite the second
side face 20D2. The second side face 20D2 and the third side
face 20D3 are perpendicular to the first direction.

[0047] The package 20 is made up of a molded article 30, a first lead 40,
a second lead 50, and a sealing resin 60.

(1) Molded Article 30

[0048] The molded article 30 forms the outer shape of the package 20. The
molded article 30 is heat resistant and has the required strength, and is
made of an electrically insulating material that does not readily
transmit outside light, the light emitted from the light emitting element
10, or other such light. A favorable example of this material is a
triazine derivative epoxy resin, which is a thermosetting resin. This
thermosetting resin may contain an acid anhydride, an antioxidant, a
parting agent, a light reflecting member, an inorganic filler, a curing
catalyst, a light stabilizer, and a lubricant. Titanium dioxide, added in
an amount of 0.1 to 90 wt %, and preferably 10 to 60 wt %, can be used as
the light reflecting member. The material of the molded article 30 is not
limited to this, however, and can be, for example, one or more types of
thermosetting resin selected from among epoxy resins, modified epoxy
resins, silicone resins, modified silicone resins, acrylate resins, and
urethane resins. Epoxy resins, modified epoxy resins, silicone resins,
and modified silicone resins are particularly favorable as the material
for the molded article 30. A thermoplastic resin may also be used, such
as a liquid crystal polymer, a polyphthalamide resin, or polybutylene
terephthalate (PBT).

(2) First Lead 40 and Second Lead 50

[0049] The first lead 40 and the second lead 50 are preferably made of a
material having a relatively high thermal conductivity (such as at least
about 200 W/(mK)). This allows any heat generated from the light emitting
element 10 to be efficiently transmitted. Examples of such a material
include one or more layers of nickel, gold, copper, silver, molybdenum,
tungsten, aluminum, iron, or another such metal, or of an iron-nickel
alloy, phosphor bronze, ferrous copper, or another such alloy. The
surfaces of the first lead 40 and the second lead 50 may also be plated.

[0050] The majority of the first lead 40 and the second lead 50 is
embedded in the molded article 30, and just parts of the first lead 40
and the second lead 50 are exposed from the molded article 30.
Specifically, just parts of the first lead 40 and the second lead 50 can
be seen from the outside of the package 20. The configuration of the
first lead 40 and the second lead 50 will be discussed below.

[0052] Next, the configuration of the leads pertaining to the embodiment
will be described through reference to the drawings. FIG. 3 is a
see-through view of FIG. 1. FIG. 4 is a see-through view of FIG. 2. FIG.
5 is a plan view of a bottom face 20A of the light emitting device 100
pertaining to the first embodiment. FIG. 6 is a plan view of the first
side face 20D1 of the light emitting device 100. In FIGS. 3 and 4, the
molded article 30 is shown in outline.

[0053] In the following description, the dimension in the first direction
is called "width," the dimension in the second direction is called
"depth," and the dimension in the third direction is called "height."

Configuration of First Lead 40

[0054] The first lead 40 is made up of a mounting part 41, a first
terminal part 42, and an exposed part 43. In this embodiment, the first
terminal part 42 and the exposed part 43 are integrally linked to the
mounting part 41. Therefore, the first terminal part 42 and the exposed
part 43 are connected mechanically and electrically to the mounting part
41. The first terminal part 42 and the exposed part 43, however, are
separated from one another, and are not directly linked.

(1) Mounting part 41

[0055] The mounting part 41 is formed in a flat shape, and is disposed
along the first side face 20D1. The first to third side faces
20D1 to 20D3 of the mounting part 41 are covered by the molded
article 30. The mounting part 41, meanwhile, has the mounting face 41A
that is exposed from the molded article 30.

[0056] The first mounting face 41A is exposed from the molded article 30
in the interior of the front face opening 20E. The light emitting element
10 is placed in the first mounting face 41A, and the first wire 11 is
also connected to the first mounting face 41A. The first mounting face
41A is sealed by the sealing resin 60 (see FIG. 1).

(2) First Terminal Part 42

[0057] The first terminal part 42 is formed in a three-dimensional shape,
and is linked to the lower end of the mounting part 41 on the second side
face 20D2 side. Part of the first terminal part 42 is exposed from
the molded article 30, and functions as an external electrode of the
light emitting device 100. The first terminal part 42 has a first end
face 42A, a second end face 42B, a third end face 42C, and a first
terminal concavity 42S.

[0058] The first end face 42A is exposed from the molded article 30 at the
first side face 20D1 of the package 20. The first end face 42A forms
part of the first side face 20D1. The second end face 42B is exposed
from the molded article 30 at the second side face 20D2 of the
package 20. The second end face 42B forms part of the second side face
20D2. The third end face 42C is exposed from the molded article 30
at the bottom face 20A of the package 20. The third end face 42C forms
part of the bottom face 20A. The first terminal concavity 42S is a
cut-out formed at the boundary between the bottom face 20A, the first
side face 20D1, and the second side face 20D2.

[0059] In this embodiment, when the light emitting device 100 is mounted,
a first solder fillet 301 is formed on the first end face 42A and the
second end face 42B, and the first terminal concave component 42S is
filled with part of the first solder fillet 301 (see FIG. 8). Also, when
the light emitting device 100 is mounted, the third end face 42C is in
contact with the mounting face 200A.

(3) Exposed Part 43

[0060] The exposed part 43 is formed in an L shape, and is linked to the
first side face 20D1 (rear face) side and the bottom face 20A side
of the mounting part 41. Part of the exposed part 43 is exposed from the
molded article 30 and functions as a heat sink.

[0061] The exposed part 43 has a first exposed face 43A, a second exposed
face 43B, and a concave component 43S (an example of a "concave
component").

[0062] The first exposed face 43A is exposed from the molded article 30 at
the first side face 20D1. The first exposed face 43A forms part of
the first side face 20D1. The surface area of the first exposed face
43A is larger than the surface area of the first end face 42A. More
specifically, as shown in FIG. 6, the height h43 of the first
exposed face 43A is greater than the height h42 of the first end
face 42A, and the width w43 of the first exposed face 43A is greater
than the width w42 of the first end face 42A.

[0063] The second exposed face 43B is exposed from the molded article 30
at the bottom face 20A of the package 20. The second exposed face 43B
forms part of the bottom face 20A. The surface area of the second exposed
face 43B is greater than the surface area of the third end face 42C. More
specifically, as shown in FIG. 5, the depth d43 of the second
exposed face 43B is the same as the depth d42 of the third end face
42C, but the width w43 of the second exposed face 43B is greater
than the width w42 of the third end face 42C.

[0064] The concavity 43S is a cut-out formed in part of the boundary
between the bottom face 20A and the first side face 20D1. Therefore,
the concavity 43S continuously opens on the bottom face 20A and the first
side face 20D1. The concave component 43S is formed so as to extend
in the first direction.

[0065] As shown in FIG. 4, the concavity 43S has a first inner wall 43Sa,
a second inner wall 43Sb, and a third inner wall 43Sc. The first inner
wall 43Sa is perpendicular to the first direction. The second inner wall
43Sb is opposite the first inner wall 43Sa. The third inner wall 43Sc is
perpendicular to the second direction and is contiguous with the first
inner wall 43Sa and the second inner wall 43Sb.

[0066] In this embodiment, when the light emitting device 100 is mounted,
the first exposed face 43A is exposed outside the light emitting device
100, and the second exposed face 43B is in contact with the mounting face
200A (see FIG. 8). When the light emitting device 100 is mounted, a
second solder fillet 303a (an example of a "second solder fillet") is
formed over the first inner wall 43Sa, and a second solder fillet 303b
(an example of a "second solder fillet") is formed over the second inner
wall 43Sb. Meanwhile, when the light emitting device 100 is mounted, the
third inner wall 43Sc is exposed on the outside of the light emitting
device 100.

[0067] In this embodiment, the exposed part 43 is electrically connected
with the mounting board 200 via a pair of second solder fillets 303a and
303b, and thereby functions as an external electrode for the light
emitting device 100 along with the first terminal part 42.

Configuration of Second Lead 50

[0068] The second lead 50 is made up of a connector 51 and the second
terminal part 52. In this embodiment, the connector 51 and the second
terminal part 52 are formed integrally.

(1) Connector 51

[0069] The connector 51 is formed in a flat shape, and is disposed along
the first side face 20D1. The first to third side faces 20D1 to
20D3 of the connector 51 are covered by the molded article 30.
Meanwhile, the connector 51 has a mounting face 51A that is exposed from
the molded article 30.

[0070] The mounting face 51A is exposed from the molded article 30 in the
interior of the front face opening 20E. The second wire 12 is connected
to the mounting face 51A. This electrically connects the connector 51 and
the light emitting element 10. The mounting face 51A is sealed by the
sealing resin 60 (see FIG. 1).

(2) Second Terminal Part 52

[0071] The second terminal part 52 is formed in a three-dimensional shape,
and is linked to an end of the connector 51. Part of the second terminal
part 52 is exposed from the molded article 30, and functions as an
external electrode of the light emitting device 100. The second terminal
part 52 has a first end face 52A, a second end face 52B, a third end face
52C, and a second terminal concavity 52S.

[0072] The first end face 52A is exposed from the molded article 30 at the
first side face 20D1 of the package 20. The first end face 52A forms
part of the first side face 20D1. The second end face 52B is exposed
from the molded article 30 at the third side face 20D3 of the
package 20. The second end face 52B forms part of the third side face
20D3. The third end face 52C is exposed from the molded article 30
at the bottom face 20A of the package 20. The third end face 52C forms
part of the bottom face 20A. The second terminal concavity 52S is a
cut-out formed at the boundary between the bottom face 20A, the first
side face 20D1, and the third side face 20D3.

[0073] In this embodiment, when the light emitting device 100 is mounted,
a third solder fillet 302 is formed on the first end face 52A and on the
second end face 52B, and the second terminal concave component 52S is
filled with part of the third solder fillet 302 (see FIG. 8). Also, when
the light emitting device 100 is mounted, the third end face 52C is in
contact with the mounting face 200A.

[0074] The surface area of the first exposed face 43A is greater than the
surface area of the first end face 52A. More specifically, as shown in
FIG. 6, the height h43 of the first exposed face 43A is greater than
the height h52 of the first end face 52A, and the width w43 of
the first exposed face 43A is greater than the width w52 of the
first end face 52A.

[0075] Also, the surface area of the second exposed face 43B is greater
than the surface area of the third end face 52C. More specifically, as
shown in FIG. 5, the depth d43 of the second exposed face 43B is the
same as the depth d52 of the third end face 52C, but the width
w43 of the second exposed face 43B is greater than the width
w52 of the third end face 52C.

Configuration of Mounting Board

[0076] Next, the configuration of the mounting board pertaining to the
first embodiment will be described though reference to the drawings. FIG.
7 is an oblique view of the mounting face of a mounting board 200
pertaining to the first embodiment. In FIG. 7, the region where the light
emitting device 100 is mounted is shown as a mounting region 100R.

[0077] As shown in FIG. 7, the mounting board 200 has the mounting face
mounting face 200A, a first land 201, a second land 202, and an
electrical circuit 204.

[0078] The light emitting device 100 is mounted on the mounting face 200A.
The first land 201 is a metal member for connecting the first terminal
part 42. The second land 202 is a metal member for connecting the second
terminal part 52. Copper foil or the like can be used, for example, as
the first land 201 and the second land 202. The surfaces of the first
land 201 and the second land 202 form part of the mounting face 200A.

[0079] The electrical circuit 204 is connected to the first land 201 and
the second land 202. Consequently, the first land 201 functions as an
external terminal corresponding to the first terminal part 42 and the
exposed part 43, and the second land 202 functions as an external
terminal corresponding to the second terminal part 52.

Configuration of Circuit Board

[0080] Next, the configuration of the circuit board pertaining to the
first embodiment will be described through reference to the drawings.
FIG. 8 is an oblique view of the mounting face of a circuit board 300
pertaining to the first embodiment.

[0081] As shown in FIG. 8, the circuit board 300 comprises the light
emitting device 100, the mounting board 200, the first solder fillet 301,
the pair of second solder fillet 303a and 303b (an example of a "second
solder fillet"), and a third solder fillets 303.

[0082] The first solder fillet 301 is formed on the mounting face 200A,
the first side face 20D1 and the second side face 20D2. The
first solder fillet 301 is held in the interior of the first terminal
concavity 42S. Consequently, the first terminal part 42 and the first
land 201 (that is the mounting board 200) are electrically and
mechanically connected.

[0083] The third solder fillet 302 is formed on the mounting face 200A,
the first side face 20D1 and the third side face 20D3. The
third solder fillet 302 is packed in the interior of the second terminal
concavity 52S. Consequently, the second terminal part 52 and the second
land 202 (that is the mounting board 200) are electrically, mechanically,
and thermally connected.

[0084] The pair of second solder fillets 303a and 303b are disposed in the
interior of the concavity 43S. More specifically, the second solder
fillet 303a is formed on the mounting face 200A and the first inner wall
43Sa, and the second solder fillet 303b is formed on the mounting face
200A and the second inner wall 43Sb. The second solder fillet 303a and
the second solder fillet 303b are opposite one another. The second solder
fillet 303a and the second solder fillet 303b mechanically and thermally
connect the exposed part 43 and the first land 201 (that is the mounting
board 200). The third inner wall 43Sc, meanwhile, is exposed on the
outside of the light emitting device 100.

Heat Dissipation Path

[0085] Next, the path of heat dissipation from the light emitting element
10 pertaining to this embodiment will be described. Four examples of a
heat dissipation path will be given, starting with the one with the
highest heat dissipation efficiency.

[0090] A method for manufacturing a plurality of the light emitting
devices 100 pertaining to the first embodiment all at once will be
described through reference to the drawings. FIG. 9A is a cross section
of a thin metal plate 451, and FIG. 9B is a plan view of the thin metal
plate 451. FIG. 10A is a cross section of a lead frame 45, and FIG. 10B
is a plan view of the lead frame 45. FIG. 11 is a detail view of the lead
frame 45. FIG. 12 is a cross section along the A-A line in FIG. 11. FIG.
13 is a plan view of a light emitting device package array PA pertaining
to this embodiment.

[0091] First, the thin metal plate 451 is readied, which has a first main
face S1 and a second main face S2 provided opposite the first main face
S1. In this embodiment, the thin metal plate 451 has a thickness t1
(such as about 0.5 mm).

[0092] Next, as shown in FIG. 9A, a first mask M1 is formed in a specific
pattern over the first main face S1, and a second mask M2 is formed in a
symmetrical pattern to the first mask M1 over the second main face S2,
and the first main face S1 and the second main face S2 are etched at the
same time. Consequently, as shown in FIG. 9B, etching holes G are formed
in the thin metal plate 451. This etching can be accomplished by dry or
wet etching. An etchant that is suitable for the material of the thin
metal plate 451 should be selected.

[0093] Next, as shown in FIG. 10A, a third mask M3 is formed in a specific
pattern over the first main face S1, and a fourth mask M4 is formed over
the second main face S2 so as to cover the entire second main face S2,
and only the first main face S1 is etched. As shown in FIG. 10B, this
completes the lead frame 45, which has etching concavities H formed in
the first main face S1. The depth of the etching concavities H is about
0.3 mm, for example. Accordingly, the portion of the thin metal plate 451
in which the etching concavities H are formed has a thickness t2
(such as about 0.2 mm) that is less than the thickness t1.

[0094] The configuration of the lead frame 45 formed in this manner will
be described in detail through reference to the drawings. As shown in
FIG. 11, the lead frame 45 has a first frame part F1, a second frame part
F2, a third frame part F3, and a fourth frame part F4.

[0095] The first frame part F1 and the second frame part F2 are adjacent
to each other in a specific direction, and are linked by a first linking
frame R1. The third frame part F3 and the fourth frame part F4 are
adjacent to each other in a specific direction, and are linked by a
second linking frame R2. The first frame part F1 and the third frame part
F3 are adjacent to each other in a perpendicular direction, which is
perpendicular to a specific direction (an example of a perpendicular
direction), and are linked by a third linking frame R3 and a fourth
linking frame R4. The second frame part F2 and the fourth frame part F4
are adjacent to each other in a perpendicular direction, and are linked
by a fifth linking frame R5 and a sixth linking frame R6.

[0096] The first to fourth frame parts F1 to F4 each have the same
configuration, and include a first thick part P1, a second thick part P2,
a first thin part Q1, and a second thin part Q2.

[0097] The first thick part P1 has a first thickness t1 (that is, the
thickness of the thin metal plate 451). In a later step, the first thick
part P1 is cut with a dicing saw to form the exposed part 43. The second
thick part P2 has the first thickness t1. The second thick part P2
is isolated from the first thick part P1 in a specific direction. In a
later step, the second thick part P2 is cut with a dicing saw to form the
first terminal part 42 and the second terminal part 52.

[0098] The first thin part Q1 has a second thickness t2 (that is, the
thickness of the portion of the thin metal plate 451 where the etching
concavities H are formed). The first thin part Q1 is linked to the first
thick part P1 and the second thick part P2. The first thin part Q1
corresponds to an outer periphery of the mounting part 41 of the light
emitting device 100. The second thin part Q2 has the second thickness
t2 (that is, the thickness of the portion of the thin metal plate
451 where the etching concavities H are formed). The second thin part Q2
is linked to the first thick part P1, and is isolated from the first thin
part Q1 via the etching holes G in a specific direction (see FIG. 9). The
second thin part Q2 corresponds to the connector 51 of the light emitting
device 100.

[0099] In this embodiment, in a plan view of the lead frame 45, a
one-sided etching concavity X, which is a part of the etching concavity
H, is formed on the inside of the first thick part P1 of each of the
frame parts F. As shown in FIG. 12, the portion of the first thick part
P1 where the one-sided etching concavities X are formed has the second
thickness t2. In a later step, the one-sided etching concavities X
are cut with a dicing saw to form the concavity 43S (see FIG. 4).

[0100] Similarly, in this embodiment, in a plan view of the lead frame
45D, a one-sided etching concavity Y, which is a part of the etching
concavity H, is formed on the inside of the second thick part P2 of each
of the frame parts F. As shown in FIG. 12, the portion of the second
thick part P2 where the one-sided etching concavities Y are formed has
the second thickness t2. In a later step, the one-sided etching
concavities Y are cut with a dicing saw to form the first terminal
concavity 42S and the second terminal concavity 52S (see FIG. 4).

[0101] In this embodiment, the first thin part Q1 of the third frame part
F3 is linked via the third linking frame R3 to the first thick part P1 of
the first frame part F1. The second thin part Q2 of the third frame part
F3 is linked via the fourth linking frame R4 to the second thick part P2
of the first frame part F1. Similarly, the first thin part Q1 of the
fourth frame part F4 is linked via the fifth linking frame R5 to the
first thick part P1 of the second frame part F2. The second thin part Q2
of the fourth frame part F4 is linked via the sixth linking frame R6 to
the second thick part P2 of the second frame part F2.

[0102] The first to sixth linking frames R1 to R6 are cut with a dicing
saw in a later step (see FIG. 13). That is, the first to sixth linking
frames R1 to R6 are cutting allowance for dicing. As shown in FIG. 11,
the portion of the first thick part P1 that is linked to the third
linking frame R3, and the portion of the second thick part P2 that is
linked to the fourth linking frame R4 are disposed in a specific
direction, and are cutting allowance for dicing as the first to sixth
linking frames R1 to R6.

[0103] Next, the lead frame 45 is disposed in a metal mold. More
specifically, the lead frame 45 is sandwiched between upper and lower
molds.

[0104] Next, the molding material that makes up the molded article 30 is
injected between the upper and lower molds.

[0105] Next, the molding material is transfer molded by being heated at a
specific temperature. As shown in FIG. 13, this completes a light
emitting device package array PA made up of the lead frame 45 and a
molded board 46 in which the lead frame 45 is embedded. Care should be
taken with the light emitting device package array PA so that the first
thick part P1 and the one-sided etching concavities X, and the second
thick part P2 and the one-sided etching concavities Y, are exposed from
the molded board 46.

[0106] Then, as shown in FIG. 13, a dicing saw is used to cut the light
emitting device package array PA along cutting lines G1 and G2 of a
specific width. This allows a plurality of light emitting devices 100 to
be manufactured all at once.

Action and Effect

[0107] (1) With the light emitting device 100 pertaining to the first
embodiment, the first lead 40 has the exposed part 43. The exposed part
43 is linked to the mounting part 41, and is exposed from the molded
article 30 at the bottom face 20A and the first side face 20D1 (rear
face).

[0108] Therefore, heat generated from the light emitting element 10 can be
directly released to the outside of the light emitting device 100 from
the first lead 40 where the light emitting element 10 is mounted. More
specifically, a second heat dissipation path going from the first exposed
face 43A to the outside air, or a third heat dissipation path going from
the second exposed face 43B to the mounting board 200 is formed.
Furthermore, when the second solder fillets 303 (the second solder fillet
303a and/or the second solder fillet 303b) are connected to the exposed
part 43, a first heat dissipation path going from the exposed part 43,
through the second solder fillet 303a, to the mounting board 200 can be
formed.

[0109] Thus, a plurality of heat dissipation paths can be formed besides a
heat dissipation path that makes use of the first terminal part 42, so
heat generated from the light emitting element 10 can be released
efficiently from the light emitting device 100.

[0110] (2) With the
light emitting device 100 pertaining to the first embodiment, the exposed
part 43 has the concave component 43S (an example of a "concave
component") whose opening is contiguous with the bottom face 20A and the
first side face 20D1.

[0111] Therefore, the pair of second solder fillets 303a and 303b can be
connected so as to straddle the inner walls 43S (the first inner wall
43Sa and the second inner wall 43Sb) from above the mounting face 200A.
Therefore, when the second solder fillets 303a and 303b solidify and
shrink, the tensile force that the second solder fillets 303a and 303b
exert on the light emitting device 100 acts on the light emitting device
100 along the first direction. Therefore, the tensile force of the second
solder fillets 303a and 303b will have less of an adverse effect on the
balance of the light emitting device 100. This effect is particularly
pronounced with a side view type of light emitting device 100 that has
the characteristic of being prone to toppling.

[0112] (3) With the
light emitting device 100 pertaining to the first embodiment, the concave
component 43S extends along the first direction. Therefore, the mutually
opposing second solder fillets 303a and 303b can be easily disposed
inside the concave component 43S. Accordingly, the tensile force exerted
by the second solder fillet 303a on the first inner wall 43Sa and the
tensile force exerted by the second solder fillet 303b on the second
inner wall 43Sb cancel each other out. As a result, the balance of the
light emitting device 100 can be further enhanced.

[0113] (4) With the
light emitting device 100 pertaining to the first embodiment, the exposed
part 43 is larger than the first terminal part 42 in a plan view of the
first side face 20D1. Therefore, the heat dissipation effect in the
above-mentioned first heat dissipation path will be greater than the heat
dissipation effect in the fourth heat dissipation path, so heat can be
dissipated from the light emitting element 10 more efficiently.

[0114]
(5) With the light emitting device 100 pertaining to the first
embodiment, the exposed part 43 is disposed on the opposite side of the
light emitting element 10 with the mounting part 41 in between.
Therefore, the distance that the heat generated by the light emitting
element 10 moves inside the mounting part 41 can be shortened.
Accordingly, thermal transfer efficiency from the light emitting element
10 to the exposed part 43 can be improved.

[0115] (6) The circuit board
300 pertaining to the first embodiment has the pair of second solder
fillets 303a and 303b (an example of "second solder fillets") connected
to the exposed part 43 and the mounting board 200. Therefore, a first
heat dissipation path is formed by the pair of second solder fillets 303a
and 303b, so heat can be transmitted efficiently from the light emitting
device 100 to the mounting board 200.

[0116] (7) With the circuit board
300 pertaining to the first embodiment, the second solder fillet 303a is
connected straddling the mounting face 200A and the first inner wall
43Sa. Similarly, the second solder fillet 303b is connected straddling
the mounting face 200A and the second inner wall 43Sb.

[0117] Therefore, when the second solder fillets 303a and 303b solidify
and shrink, the tensile force that the second solder fillets 303a and
303b exert on the light emitting device 100 acts on the light emitting
device 100 along the first direction. Therefore, the tensile force of the
second solder fillets 303a and 303b will have less of an adverse effect
on the balance of the light emitting device 100. This effect is
particularly pronounced with a side view type of light emitting device
100 that has the characteristic of being prone to toppling.

SECOND EMBODIMENT

[0118] Next, a second embodiment will be described through reference to
the drawings. The difference between the first and second embodiments is
that the interior of the concave component 43S is divided up into a
plurality of spaces. The following description will focus on this
difference.

Configuration of Light Emitting Device

[0119] FIG. 14 is a see-through oblique view of the light emitting device
100 pertaining to the second embodiment as seen from behind. As shown in
FIG. 14, the exposed part 43 of the light emitting device 100 has a first
partition 431, a second partition 432, a first solder holder 433, a
second solder holder 434, and a third solder holder 435. In this
embodiment, the first partition 431, the second partition 432, the first
solder holder 433, the second solder holder 434, and the third solder
holder 435 constitute the concave component 43S.

[0120] The first partition 431 and the second partition 432 each divide
the interior space of the concave component 43S into two spaces in the
first direction. Therefore, in this embodiment the interior space of the
concave component 43S is divided into three spaces.

[0121] The first solder holder 433, the second solder holder 434, and the
third solder holder 435 respectively encompass the three spaces divided
up by the first partition 431 and the second partition 432.

[0122] Although not depicted in the drawings, the second solder fillet
303a is disposed in the first solder holder 433, and the second solder
fillet 303b is disposed in the third solder holder 435. The second solder
fillet 303a is blocked by the first partition 431, and does not flow into
the second solder holder 434. The second solder fillet 303b is blocked by
the first partition 431, and does not flow into the second solder holder
434. Another solder fillet (not shown) is disposed in the second solder
holder 434.

Method for Manufacturing Light Emitting Device

[0123] First, a lead frame 45A is readied as shown in FIG. 15. The lead
frame 45A comprises a first partition base 431A, a second partition base
431A, a first solder holder base 433A, a second solder holder base 434A,
and a third solder holder base 435A.

[0124] This lead frame 45A can be formed by setting a narrow region in
which one-sided etching is performed on a thin metal plate. More
specifically, the first partition base 431A and the second partition base
431A are formed by subjecting the region in which the first solder holder
433, the second solder holder 434, and the third solder holder 435 are
formed to one-sided etching to the same depth as the first terminal
concave component 42S and the second terminal concave component 52S.

[0125] Next, the lead frame 45A is embedded in the molded board 46 (see
FIG. 13) by transfer molding.

[0126] Next, a dicing saw is used to cut the lead frame 45A and the molded
board 46 along a cut line of a specific width (see FIG. 13).

Action and Effect

[0127] With the light emitting device 100 pertaining to the second
embodiment, the exposed part 43 has the first partition 431 and the
second partition 432 that divide up the interior of the concave component
43S into two spaces.

[0128] Therefore, with the light emitting device 100 pertaining to the
second embodiment, the second solder fillet 303a is held in the first
solder holder 433 by the first partition 431, and the second solder
fillet 303b is held in the third solder holder 435 by the second
partition 432. Accordingly, the pair of second solder fillets 303a and
303b will spread out less inside the concave component 43S, and this
further improves the balance of the light emitting device 100. Also,
since another solder fillet can be disposed in the second solder holder
434, the heat dissipation efficiency of the light emitting device 100 can
be further enhanced.

THIRD EMBODIMENT

[0129] Next, a third embodiment will be described through reference to the
drawings. The difference between the first and third embodiments is that
the exposed part 43 functions as an external terminal. The following
description will focus on this difference.

Configuration of Mounting Board

[0130] FIG. 16 is an oblique view of the mounting board 200 pertaining to
the third embodiment. As shown in FIG. 16, the mounting board 200 has a
third land 203. The third land 203 is separated from the first land 201
and the second land 202, and is electrically isolated from the electrical
circuit 204.

Configuration of Circuit Board

[0131] FIG. 17 is an oblique view of the circuit board 300 pertaining to
the third embodiment. As shown in FIG. 17, when the light emitting device
100 is mounted on the mounting board 200, the exposed part 43 is
mechanically and thermally connected to the third land 203 by the pair of
second solder fillets 303a and 303b.

[0132] Also, the exposed part 43 is electrically connected to the third
land 203 via the pair of second solder fillets 303a and 303b, but since
the third land 203 is electrically isolated from the electrical circuit
204, the exposed part 43 does not function as an external terminal.

FOURTH EMBODIMENT

[0133] Next, a fourth embodiment will be described through reference to
the drawings. The difference between the first and fourth embodiments is
that a part of the second lead 50 extends toward the first side face
20D1. The following description will focus on this difference.

Configuration of Light Emitting Device

[0134] FIG. 18 is an oblique see-through view of a light emitting device
100 pertaining to a fourth embodiment, as seen from the rear. As shown in
FIG. 18, with the light emitting device 100, the second lead 50 has a
first extension 101.

[0135] The first extension 101 is disposed on the connector 51, and is
connected to the second terminal part 52. The first extension 101 extends
from the surface of the connector 51 on the first side face 20D1
side, toward the first side face 20D1, and is exposed from the
molded article 30 at the first side face 20D1. The first extension
101 has a first extension face 101S that forms part of the first side
face 20D1.

Method for Manufacturing Light Emitting Device

[0136] First, the lead frame 45B shown in FIG. 19 is readied. The lead
frame 45B comprises a first extension base 101A. This lead frame 45B can
be formed by setting the region in which one-sided etching is performed
in order to form a connection base 51A in C-Shape.

[0137] Next, the lead frame 45B is embedded in a molded board 46 (see FIG.
13) by transfer molding.

[0138] Next, the lead frame 45B and the molded board 46 are cut along the
cutting line (see FIG. 13) having a specific width with a dicing saw.

Action and Effect

[0139] With the light emitting device 100 pertaining to the fourth
embodiment, the second lead 50 has the first extension 101. The first
extension 101 is disposed on the connector 51 and connected to the second
terminal part 52. The first extension 101 is exposed from the molded
article 30 at the first side face 20D1.

[0140] Since the first extension 101 is thus exposed from the molded
article 30 at the first side face 20D1, a heat dissipation path of
"light emitting element 10→molded article 30→second wire
12→connector 51 first extension 101→first extension face
101S→outside air" can be formed. Accordingly, heat generated from
the light emitting element 10 can be released more efficiently from the
light emitting device 100.

[0141] Also, since the first extension 101 is connected to the second
terminal part 52, a heat dissipation path of "light emitting element
10→molded article 30→second wire 12→connector
51→first extension 101→second terminal part
52→mounting board 200" can be formed. Accordingly, heat generated
from the light emitting element 10 can be released more efficiently from
the light emitting device 100.

[0142] Also, the first extension face 101S is exposed at the outermost
face of the molded article 30. Specifically, in the process of
manufacturing the molded article 30, the first extension 101 hits the
inner face of the mold. Consequently, since the connector 51 is supported
by the first extension 101, the tiny vibrations of the connector 51
caused by the injected resin material can be suppressed. Therefore, the
resin material can work its way evenly around the connector 51, so there
is better adhesion between the molded article 30 and the second lead 50.

FIFTH EMBODIMENT

[0143] Next, a fifth embodiment will be described through reference to the
drawings. The difference between the fourth and fifth embodiments is that
part of the first lead 40 also sticks out toward the first side face
20D1 (rear face). The following description will focus on this
difference.

Configuration of Light Emitting Device

[0144] FIG. 20 is an oblique see-through view of a light emitting device
100 pertaining to a fifth embodiment, as seen from the rear. As shown in
FIG. 20, with the light emitting device 100, the first lead 40 has a
second extension 102, and the second lead 50 has a first extension 101.

[0145] The configuration of the first extension 101 is as described above
in the fourth embodiment.

[0146] The configuration of the second extension 102 is the same as the
configuration of the first extension 101. The second extension 102 is
disposed on the mounting part 41, and is connected to the first terminal
part 42. The second extension 102 extends from the surface of the
mounting part 41 on the first side face 20D1 side toward the first
side face 20D1, and is exposed from the molded article 30 at the
first side face 20D1. The second extension 102 has a second
extension face 102S that forms part of the first side face 20D1.

Method for Manufacturing Light Emitting Devices

[0147] First, the lead frame 45C shown in FIG. 21 is readied. The lead
frame 45 C comprises a first extension base 101A and a second extension
base 101B. This lead frame 45C can be formed by setting the region in
which one-sided etching is performed in order to form a first connection
base 41A and a second connection base 51A, as shown in FIG. 21.

[0148] With the lead frame 45C pertaining to this embodiment, the
one-sided etching concavities X and the one-sided etching concavities Y
are set to be larger than the lead frame 45 pertaining to the first
embodiment. This raises the dimensional machining limit at which
one-sided etching.

[0149] Thus, the lead frame 45C pertaining to this embodiment has a
fundamentally different configuration from that of the lead frame 45
pertaining to the first embodiment. The detailed configuration of the
lead frame 45C will now be described through reference to the drawings.
FIG. 22 is a detail view of the lead frame 45C. As shown in FIG. 22, the
lead frame 45C has first to fourth frame parts F1 to F4. The first frame
part F1 and the second frame part F2 are adjacent to each other in a
specific direction, but are not linked. Similarly, the third frame part
F3 and the fourth frame part F4 are adjacent to each other in a specific
direction, but are not linked.

[0150] In this embodiment, the third frame part F3 and the fourth frame
part F4 are disposed in rotational symmetry with respect to the first
frame part F1 and the second frame part F2 around an axis T that is
parallel to the thickness direction (a direction that is perpendicular to
the specific direction and the perpendicular direction, that is, a
direction that is perpendicular to the plane of the drawing). The first
thick part P1 of the third frame part F3 is directly linked to the first
thick part P1 of the first frame part F1. The second thick part P2 of the
third frame part F3 is directly linked to the second thick part P2 of the
second frame part F2. The second thick part P2 of the fourth frame part
F4 is directly linked to the second thick part P2 of the first frame part
F1.

[0151] Also, in this embodiment, in a plan view of the lead frame 45D,
part of the etching concavities H is formed on the inside of the first
thick part P1 of the frame parts F. Consequently, the one-side etching
concavities X are formed by linking the first thick part P1 of the third
frame part F3 and the first thick part P1 of the first frame part F1.

[0152] In this embodiment, in a plan view of the lead frame 45D, part of
the etching concavities H is formed on the inside of the second thick
part P2 of the frame parts. Consequently, the one-side etching
concavities Y are formed by linking the second thick part P2 of the first
frame part F1 and the second thick part P2 of the fourth frame part F4.
Also, the one-side etching concavities Y are formed by linking the second
thick part P2 of the second frame part F2 and the second thick part P2 of
the third frame part F3.

[0153] The portion where the first thick part P1 of the third frame part
F3 and the first thick part P1 of the first frame part F1 are linked
constitutes a cutting allowance for dicing (see FIG. 23). Similarly, the
portion where the second thick part P2 of the third frame part F3 and the
second thick part P2 of the second frame part F2 are linked constitutes a
cutting allowance for dicing. The portion where the second thick part P2
of the fourth frame part F4 and the second thick part P2 of the first
frame part F1 are linked also constitutes a cutting allowance for dicing.

[0154] Next, as shown in FIG. 23, the light emitting device package array
PA is completed by embedding the lead frame 45C in a molded board 46 by
transfer molding. It should be noted that the first thick part P1 and the
one-side etching concavities X, and the second thick part P2 and the
one-side etching concavities Y are exposed from the molded board 46 in
the light emitting device package array PA.

[0155] Next, as shown in FIG. 23, the light emitting device package array
PA is cut with a dicing saw along cutting lines H1 and H2 having a
specific width.

Action and Effect

[0156] With the light emitting device 100 pertaining to the fifth
embodiment, the first lead 40 has the second extension 102. The second
extension 102 is disposed on the mounting part 41 and connected to the
first terminal part 42. The second extension 102 is exposed from the
molded article 30 at the first side face 20D1.

[0157] Since the second extension 102 is thus exposed from the molded
article 30 at the first side face 20D1, a heat dissipation path of
"light emitting element 10→mounting part 41→second
extension 102→second extension face 102S→outside air" can
be formed. Accordingly, heat generated from the light emitting element 10
can be released more efficiently from the light emitting device 100.

[0158] Also, since the second extension 102 is connected to the first
terminal part 42, a heat dissipation path of "light emitting element
10→mounting part 41→second extension 102→first
terminal part 42→mounting board 200" can be formed. Accordingly,
heat generated from the light emitting element 10 can be released more
efficiently from the light emitting device 100.

[0159] Also, the second extension face 102S is exposed at the outermost
face of the molded article 30. Specifically, in the process of
manufacturing the molded article 30, the second extension 102 hits the
inner face of the mold. Consequently, since the mounting part 41 is
supported by the second extension 102, the tiny vibrations of the
mounting part 41 caused by the injected resin material can be suppressed.
Therefore, the resin material can work its way evenly around the mounting
part 41, so there is better adhesion between the molded article 30 and
the first lead 40.

[0160] The effect produced by the second lead 50 having the first
extension 101 is the same as described in the fourth embodiment above.

Other Embodiments

[0161] The present invention was described by the above embodiments, but
the text and drawings that make up part of this disclosure should not be
construed as limiting this invention. Various alternative embodiments,
working examples, and applied technology will be apparent to a person
skilled in the art from this disclosure.

[0162] (A) In the above
embodiment, a so-called side view type of light emitting device 100 was
described, but this is not the only option, and the exposed part 43 can
also be applied to a so-called top view type of light emitting device in
which light that is perpendicular to the mounting face 200A is emitted
from the light emitting element 10.

[0163] (B) In the above embodiments,
the exposed part 43 had the concavity 43S, but this is not the only
option. The exposed part 43 need not have the concavity 43S. Here again,
heat can be effectively dispersed from the first exposed face 43A and the
second exposed face 43B.

[0164] (C) In the above embodiment, the pair of
second solder fillets 303a and 303b was formed, but this is not the only
option. For example, just one of the second solder fillets 303a and 303b
may be formed, or another solder fillet may be formed in addition to the
pair of second solder fillets 303a and 303b. The greater is the number of
solder fillets, the more securely the light emitting device 100 and the
mounting board 200 can be connected.

[0165] (D) In the above embodiment,
the second solder fillets 303a and 303b were separated from one another
in the concave component 43S, but this is not the only option. The second
solder fillets 303a and 303b may be linked to one another. Specifically,
a single second solder fillet 303 may be formed that extends in the first
direction from the first inner wall 43Sa to the second inner wall 43Sb.
This improves adhesion between the light emitting device 100 and the
mounting board 200, and further enhances the efficiency of heat
dissipation from the exposed part 43 to the mounting board 200.

[0166]
(E) In the above embodiment, the light emitting device 100 comprised just
one light emitting element 10, but this is not the only option. The light
emitting device 100 may comprise a plurality of light emitting elements
10 that are linked together. In this case, the light emitting elements 10
may all be the same type, or different types emitting in red, green, and
blue (the three primary colors of light) may be combined.

[0167] (F) In
the above embodiment, the outer shape of the light emitting device 100
was substantially cuboid, having six sides (the bottom face 20A, the top
face 20B, the front face 20C, the first side face 20D1, the second
side face 20D2, and the third side face 20D3), but this is not the
only option. The light emitting device 100 need only have a bottom face
and at least one side face. Therefore, the outer shape of the light
emitting device 100 may be that of a circular cylinder or an elliptical
cylinder.

[0168] (G) In the above embodiment, the mounting part 41 was
formed in a flat shape, the exposed part 43 was formed in an L shape, and
the first terminal part 42 and the second terminal part 52 were formed in
cuboid shapes, but this is not the only option. The outer shape and so
forth of the light emitting device 100 can be varied as needed.

[0169]
(H) In the above embodiment, the lead frame 45A was formed by etching a
thin metal plate, but this is not the only option. For example, the lead
frame 45A can be formed by punching out a plurality of thin metal plates
into the desired shape and then press-fitting them together.

[0170] Thus, the present invention of course encompasses various
embodiments, etc., that are not discussed herein. Therefore the
technological scope of the present invention is defined only by the
invention-defining matters pertaining to the appropriate claims from the
above description.

[0171] The technology disclosed herein can be utilized in the field of
light emitting devices because it allows heat to be dissipated
efficiently from a light emitting element.